The Lagoon Nebula

About This Photograph

Deep in the heart of the constellation of Sagittarius is a classic deep-sky object, the Lagoon Nebula. It is also known as "Messier 8," or "M8" for short, after French astronomer and comet hunter Charles Messier, who included it in his catalog of objects that are not comets. This patch of glowing gas probably appeared very similar to a comet when first seen, but the fact that it does not drift across the sky like comets do is the clue that it is something entirely different. In actuality, it is a vast cloud of glowing gas, some 140 light years (820 trillion miles) across. It is a stellar nursery, a birthplace of new stars, and it glows due to the close proximity of bright, blue stars newly hatched and gleaming brilliantly with ultraviolet radiation. This light from the newborn stars causes the gas to fluoresce, or glow, in colors visible to our eyes.